How to Repair Cracks and Loose Plaster in a Concrete Swimming Pool

Karin Mangan

As summer arrives, it's time to carry out a few minor pool repairs before you take a well-earned dip.

To repair a small crack (less than 1 foot long or 1/8 inch wide):

  • Use a grinder to extend the depth of the crack to ½ inch and the length by an inch each side, which allows the repair compound to hold firmly.
  • Wipe dust and debris away, then apply caulk along the length of the crack, leaving about ¼ inch for the epoxy compound to be added later.
  • When the caulk is dry, apply an epoxy compound manufactured for the purpose, which you can find at most hardware stores. Moisten the surface of the crack and apply the compound with a putty knife or flat trowel.
  • Make sure there is no air inside the crack.
  • Fill the pool with water as soon as possible to prevent the repair from cracking.

To repair loose plaster:

  • Remove visibly loose plaster with a hammer and chisel. Tap the pool floor gently with a hammer to find hollow plaster that will soon become loose, and chip that up too.
  • Use your chisel to dig small holes in the surface around where the plaster is damaged. This helps the new plaster adhere.
  • Acid rinse the surface you intend to repair.
  • Apply an epoxy compound, available at most hardware stores. You may need to add a concrete dye to match the color of your pool.
  • Moisten the surface and apply the compound with a flat trowel or putty knife, making sure it gets into all the spaces and no air bubbles are left.
  • Allow about 15 minutes, then smooth the area again.
  • Fill the pool as soon as possible and keep the repair moist in the meantime to prevent cracking.

Now that's done, jump in and enjoy.

About the Author

Karin has worked as a freelancer for over ten years, writing informatively about a wide range of subjects. She has a PhD and a background in education and research.

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